LeCroy Introduces High End Serial Data Analyzer with X-Stream Technology for Real Time Analysis of High-speed Complex Data Rates 

Last October LeCroy Corporation introduced three versions of a Serial Data Analyzer, models SDA 6000 (6 GHz signal capture bandwidth for data rates up to 3.5 Gbits/sec) and SDA 5000 (5 GHz signal capture bandwidth for data rates up to 2.5 Gbits/sec) and SDA3000 (3 GHz bandwidth for data rates up to 1.5 Gbits/sec). Now LeCroy is launching an upgraded version of its highest performance product. The new model SDA 6020 is targeted to engineers designing serial ATA, Xaui, Infiniband and other types of multi-lane serial data signals. It can capture four simultaneous signals at 20 GS/s sampling rate in real time. This also makes the SDA6020 ideal for engineers who design computational systems which include microprocessors, memory arrays and other crucial signals which need to be captured at highest sample rate on four simultaneous channels. In addition to its value as a serial data analysis instrument, the SDA6020 is the also the world’s best real time digital oscilloscope--with 6 GHz bandwidth, a 20 GS/s ADC on each channel and up to 48 million points of memory per channel. The SDA series also incorporates LeCroy X-Stream Technology that performs analysis 10-100 times faster and allows the user to insert customized measurements into the processing stream of the instrument. Altogether, this is the best instrument available for engineers who do Serious Data Analysis.

Previous generations of oscilloscope products from all vendors used a "single bit per" method to capture information from a serial data stream. On each trigger the scope would capture data from one bit and put the data sample(s) onto the screen. By triggering many hundreds of thousands, or millions, of times the scope would build up a persistence display of an eye pattern of the signal. Such a display would show the noise and timing jitter of the data bits relative to the clock but it also included ten’s of picoseconds of trigger jitter and, if a hardware circuit was used to recover the clock, it also contained CDR jitter. The SDA’s high sampling rate, long memory and advanced processing engine allow it to conduct extremely accurate single shot measurements, in which up to 8,000,000 consecutive bits can be captured with zero deadtime. This means engineers testing data patterns up to 223 bits can capture all of the bits in a single trigger—with 100% confidence that every bit has been captured exactly once. There is enough information to recover the clock numerically rather than using a hardware CDR circuit. With this technique there is zero trigger jitter and much smaller CDR jitter. The result is a much cleaner view and more accurate measurements of serial data signals.

In addition to having higher confidence level that all bits in a pattern have been tested, cleaner eye diagrams and more accurate measurements, the continuous bit capture method offers unique new troubleshooting tools. When comparing the bits to an industry standard test template, the failed bits by are shown with red circles around them. The user is told which bits failed and is shown the failed bits plus the signal wave shape surrounding the failed bits. Since the entire bit stream has been captured, an engineer can look at each failed bit and, for example, the ten bits that preceded it and the ten bits that trailed it in the test pattern. This technique is called Mask Testing with Violation Locator.

Another new tool allows engineers to directly view and measure inter-symbol interference. This data dependent jitter can be a very important component of the deterministic jitter in high-speed serial data systems. The ISI plot is built by capturing a long set of continuous bits and examining each data pattern. For example, if the engineer would like to look at every combination of 5 data bits there are 32 such patterns. In a data stream of 32,000 bits, each pattern will occur approximately 1,000 times. Each time a particular pattern occurs, that wave shape is added to an averaging buffer. The result is 32 averaging buffers which show very clean waveforms of every possible five bit data pattern—with very little random jitter. The SDA can then display the averaged waveforms and measure the difference caused by inter-symbol interference in the shapes of 1s and 0s in different patterns.

LeCroy has designed the SDA series specifically for analyzing the high data rates found in optical and high speed electrical serial data systems. It can conduct a number of measurements, including jitter (Tj, Rj, Dj and the subcomponents of deterministic jitter), noise, duty cycle, overshoot, undershoot, extinction ratio, Q-factor, mean optical power, and amplitude. Mask testing of SONET/SDH, gigabit Ethernet, and other standards can also be conducted. Not only can these measurements be made accurately, they can be conducted 10 ~ 100 times faster than with any other similar type of digitizer based communications analyzer presently on the market.

The SDA series makes it easy to accurately and reliably perform measurements on high speed serial data streams. A wide range of target applications include computer (and computer component) design/validation, testing of high speed differential electrical links and capture/analysis of optical signals (up to and including OC-48). In addition to locating signal degradation problems, it can also trace the problem back to its origin, allowing for the comprehensive analysis of serial data streams, telecommunications components, transceiver subassemblies and transmission systems. Optional accessories include optical to electrical converters and reference receivers with optical bandwidth above 4 GHz.

The SDA series can conduct precise and complex measurements quickly due to the incorporation of LeCroy’s X-StreamTM Technology, an extremely fast streaming architecture for handling and analyzing data. It enables high data throughput even when performing complex measurements and long data arrays. The front end of the X-Stream Technology starts with the output of the 20 GS/s ADC on each channel which, since each data sample is eight bits, constitutes a stream of 20 Gbytes of data per second. Each of four channels streams this data in real time into "super fast" CMOS memory chips that can accept the 20 Gbytes/sec data rate for up to 48 million points of acquisition. This acquisition memory is a proprietary LeCroy design that performs a variety of operations. It packetizes the data from the ADC and transfers the packets in a streaming mode via dual high-speed data busses to the CPU board. At that point, the operating system optimizes the possibility that the analysis algorithms and data packets are simultaneously resident in cache so that calculations can be performed extremely fast.

Using X-Stream Technology, a long complex waveform can be under analysis by the CPU while the next signal is flowing through the front end of the streaming architecture. The X-Stream Technology software algorithms enable data packets and the analysis routines for performing measurements on those packets to be simultaneously resident in the microprocessor cache. This allows complex signal analysis to be conducted on packet data 10 to 100 times faster than older technologies which rely on moving data to the microprocessor from RAM. The user can also create custom measurements using MATLAB, Mathcad, Excel or Visual Basic scripts and insert the new waveform math functions or parameter measurements directly into the processing stream of the scope. This allows the user to have fast, customized processing and use all the tools of the scope such as histograms, parameter tracks, FFT or persistence displays even when doing customized analysis. The custom measurement becomes part of the scope. Of course, the user can also export data out of the oscilloscope application into third party software packages just as in any other Open Windows type of DSO.

LeCroy has also designed a series of O/E converters with advanced semiconductor technology. These O/E converters have responsiveness in excess of 1V/mW covering a wavelength range of 950 nm ~ 1630 nm and have optical bandwidths in excess of 4 GHz. They can be used in conjunction with the SDA to test optical communications signals at data rates of 2.5 Gb/s.

Complementing these O/E converters are reference receivers, which use DSP to implement the reference receiver filter. The filter coefficients are computed using the known response of the O/E converter. The O/E response characteristics are stored in a memory chip within the O/E housing. An SDA can dynamically match the response characteristics of the O/E with those of any input channel, allowing the O/E to be moved to any channel on the SDA, moved to another SDA, or to have up to four simultaneous reference receivers on an SDA—none of these capabilities have been previously possible with any test instrument. This capability offers a tremendous advantage for manufacturing up time since repairs and calibrations can be performed separately on individual components and throughput can be increased an additional factor of four (by using four reference receivers) in addition to the throughput gains from X-Stream. An added advantage to the digital reference receivers is their ability to support an arbitrary data rate.

The powerful user interface in the SDA presents the user with a comprehensive display of the key measurements required by all optical and electrical serial data signals. Eye pattern, jitter, bit error rate and waveform parameters are displayed in one easy to read display. By displaying these key measurements together, the user can quickly determine compliance with standards as well as locate the sources of errors. Design debugging throughput is enhanced by the integrated measurement capability of the SDA since it is not necessary to measure eye pattern, jitter and bit error rate on separate instruments. The deep memory and fast sampling rate of this instrument allow the capture and display of data sequences as large as 223 bits which enables users to evaluate pattern dependent problems without the need for special triggers or signal sources.

• Jitter and Timing Analysis Package
• Prolink
• Adapter SMA (4)
• Prolink BNC Adapter (2)
• SVGA touch screen
• CD ROM Drive
• Floppy Disk Drive
• Operator’s Manual
• Quick Reference Guide
• CDROM with Remote Control Manual, utilities and recovery software
• Protective Front cover
• SVGA video, 10/100BaseT, parallel and USB ports
• Optical 3 button wheel mouse
• 3-year warranty
• Performance certificate

Delivery is 8-10 weeks ARO.

Engineers who would like more information can call 800-4LECROY (800-453-2769) or visit www.lecroy.com.

LeCroy, a U.S. corporation established in 1964, designs, manufactures and markets digital storage oscilloscopes, analog oscilloscopes and waveform digitizer instrumentation. Manufacturing facilities are located at corporate headquarters in Chestnut Ridge, NY. Direct sales and service offices are located throughout the United States, in all major European countries, and throughout Asia.

Media contact: Patrick Brightman, SG&W (973) 263-5475

Editors' Technical contact: Dr. Michael Lauterbach, LeCroy (845) 578-6057

Customer contact: LeCroy Customer Care Center (800) 453-2769

Website: www.lecroy.com